Mobile station apparatus, base station apparatus, and mobile communication system

ABSTRACT

A mobile station (MS) includes a first circuitry configured to: select a cell by a cell selection procedure started by the MS, in a case where a radio link failure is detected, wherein said selecting based is on: a criteria of the cell selection procedure; information, used for indicating access restrictions of the MS, the information broadcasted on each cells; and an access class of the MS, wherein the access class being either: a first access class applied for an emergency call, or other access classes applied for other calls; and treat, in a case where the radio link failure is detected upon communication of the first access class, the selected cell as an appropriate cell even in a case where the selected cell is a cell belonging to a first base station not registered in the list; and a second circuitry configured to access the appropriate cell.

This application is a Divisional of co-pending application Ser. No.12/997,830 filed on. Jan. 14, 2011, and for which priority is claimedunder 35 U.S.C. §120, application Ser. No. 12/997,830 is the nationalphase of PCT International Application No. PCT/2009/059767 filed on May28, 2009 under 35 U.S.C. §371, which claims the benefit of priority ofJP2008-153427 filed Jun. 11, 2008. The entire contents of each of theabove-identified applications are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a mobile communication technologyincluding a small base station apparatus that makes only mobile stationapparatuses registered in advance accessible in normal case, and on theother hand, makes unregistered mobile station apparatuses accessible innon-normal case.

BACKGROUND ART

Conventionally, discussions have been made on small base stationapparatuses to be installed in homes or offices. A small base stationapparatus is used for connection with fixed lines for homes to widen thecommunication area or provide user-specific services. A small basestation apparatus according to the standardization group 3GPP (3rdGeneration Partnership Project) is called a home node B (or a home (e)node B). Among home nodes B, a home node B that limits users who can usethe node by prior registration of access-permitted users, isparticularly called a CSG (Closed Subscriber Group) cell (Non-PatentDocument 1).

In 3GPP, a discussion is progressing on a CSG cell for ‘EUTRA (EvolvedUniversal Terrestrial Radio Access)’ having been evolved from the thirdgeneration mobile communication system and ‘Advanced EUTRA’ advancedtherefrom. Unless a mobile station apparatus can distinguish among CSGcells for which subscribers are registered, CSG cells for whichsubscribers are not registered, and normal cells, the mobile stationapparatus tries access to inaccessible CSG cells, resulting in a wasteof power consumption and radio resources.

Further, because handover to a cell other than the registered CSG cellsis not normally permitted for a mobile station apparatus, it isnecessary for the mobile station apparatus to recognize a type of thecell in advance. As methods for a mobile station apparatus todistinguish CSG cells from normal cells, there are proposed methods,including a method that includes a CSG cell identifier in broadcastinformation (section 6.3.1 of Non-Patent Document 2), a method thatperforms distinguishing with a cell ID judged by a synchronizationsignal (Non-patent Document 3), and a method that allocates to a CSGcell a frequency different from that to a normal cell (Non-patentDocument 4).

FIG. 17 is a diagram showing an example of a sequence chart thatillustrates the measurement of a neighboring cell and a measurementreport by a mobile station apparatus, when a CSG cell is disposed as aneighboring cell. The mobile station apparatus receives asynchronization signal-s (step S1701), a downlink reference signal-s(step S1702), and broadcast information channel-s (step S1703) from abase station apparatus (source cell), and then starts communication withthe source cell (step S1704), wherein the mobile station apparatus andthe source cell are in a state of communication with each other (activestate).

Herein, the mobile station apparatus obtains CSG cell information fromthe neighboring CSG cell deployed in the mobile station apparatus (stepS1705). CSG cell information is information obtained by the mobilestation apparatus from a signal transmitted from a CSG cell by a methodaccording to any one of Non-Patent Documents 2 to 4, to distinguish anormal cell from a CSG cell. For example, in Non-Patent Document 2, CSGcell information indicates a CSG cell identifier of broadcastinformation. Likewise, in Non-Patent Documents 3 and 4, CSG cellinformation respectively corresponds to a cell ID and a frequency band.

The mobile station apparatus, in neighboring cell measurement processing(step S1706), recognizes a CSG cell by a CSG cell identifier, eliminatesunregistered CSG cells from target base station apparatuses ofneighboring cell measurement, and transmits a measurement report, whichis a radio signaling message, to the source cell without including theCSG cells in a measurement report message (step S1707). That is, themobile station apparatus does not perform measurement processing ofdownlink reference signals of the unregistered CSG cells.

FIG. 18 is a diagram showing an example of a flowchart illustrating theoperation of the mobile station apparatus in the measurement processingof neighboring cells. The mobile station apparatus receives neighboringcell signals from the neighboring cells (step S1801). From a result ofreception and demodulation of the neighboring cell signals, it isdetermined by CSG cell identifiers whether unregistered CSG cells areincluded in the neighboring cells (step S1802), and when unregisteredCSG cells are included, the measurement processing of the downlinkreference signals of the CSG cells is stopped on the unregistered CSGcells (step S1803). On the other hand, when it is determined that nounregistered CSG cells are included in step S1802, then the measurementprocessing of measurement signals is executed on all the neighboringcells (step S1804).

PRIOR ART DOCUMENTS Non-Patent Documents

-   Non-Patent Document 1: 3GPP TS36.300, Overall description; Stage 2.    V8.4.0 http://www.3gpp.org/ftp/Specs/html-info/36300.htm-   Non-Patent Document 2: 3GPP TS36.331, Radio Resource    Control(RRC);Protocol specification. V8.1.0    http://www.3gpp.org/ftp/Specs/html-info/36331.htm-   Non-Patent Document 3: NTT DoCoMo, R2-073374, 3GPP TSG-RAN2 Meeting    #59, Athens, Greece, 20-24 Aug. 2007-   Non-Patent Document 4: Samsung, R2-073307, 3GPP TSG-RAN2 Meeting    #59, Athens, Greece, 20-24 Aug. 2007

DISCLOSURE OF THE INVENTION Summary of the Invention Problems to beSolved by the Invention

In conventional technologies as described above, Since a mobile stationapparatus does not report on unregistered CSG cells, unnecessarymeasurement of CSG cells and unnecessary handover are restricted, andthe power consumption by the mobile station apparatus is reduced.However, by the conventional technologies, even for communication of atype to be prioritized over normal calls at the time of originated callof a priority call (emergency call or emergency communication) or at thetime of handover, the measurement result of CSG cells is not reported toa base station apparatus. Consequently, even when the radio quality of aCSG cell in the vicinity is adequate, the mobile station apparatuscannot select the CSG cell as a handover destination. As a result, thereis a problem that the range of coverage decreases and the probability ofcall loss and call disconnection increases.

The present invention has been developed in view of these circumstances,and an object thereof is to provide a mobile station apparatus, a basestation apparatus, and a mobile communication system capable ofrealizing a measurement method of a CSG cell which is appropriate in acase where communication of a type, such as a priority call, to beprioritized over normal calls has occurred.

Means for Solving the Problems

(1) To attain the above-described object, the following means have beendevised in the invention. That is, a mobile station apparatus inaccordance with the invention is a mobile station apparatus applied to amobile communication system that includes an access-restricted basestation apparatus for performing communication with a mobile stationapparatus registered in advance and a mobile station apparatus in apriority call communication, wherein the mobile station apparatusdetermines, based on a priority of the communication of the mobilestation apparatus, whether or not to transmit a measurement result of atransmission signal from the access-restricted base station apparatus asmeasurement report information, the measurement result being used formobility control of the mobile station apparatus in communication.

(2) Further, in the mobile station apparatus in accordance with theinvention, the mobile station apparatus, if the priority of thecommunication is high, transmits the measurement result of thetransmission signal from the access-restricted base station apparatus asthe measurement report information, and on the other hand, if thepriority of the communication is low, does not transmit the measurementresult of the transmission signal from the access-restricted basestation apparatus as the measurement report information.

(3) Still further, in the mobile station apparatus in accordance withthe invention, in a case of performing reconnection, the mobile stationapparatus determines whether or not the access-restricted base stationapparatus is selectable as a reconnection cell, based on the priority ofthe communication having been performed just before the reconnection.

(4) Yet further, in the mobile station apparatus in accordance with theinvention, the mobile station apparatus, if the priority of thecommunication is high, determines the access-restricted base stationapparatus to be selectable as the reconnection cell, and on the otherhand, if the priority of the communication is low, determines theaccess-restricted base station apparatus to be not selectable as thereconnection cell.

(5) Further, in the mobile station apparatus in accordance with theinvention, when the mobile station apparatus determines theaccess-restricted base station apparatus to be selectable as thereconnection cell and the transmission signal from the access-restrictedbase station apparatus has a best reception quality, the mobile stationapparatus selects the access-restricted base station apparatus as thereconnection cell.

(6) Still further, a mobile station apparatus in accordance with theinvention is a mobile station apparatus applied to a mobilecommunication system that includes an access-restricted base stationapparatus for performing communication with a mobile station apparatusregistered in advance and a mobile station apparatus in a priority callcommunication, wherein the mobile station apparatus, when havingreceived, from a base station apparatus in a priority callcommunication, priority-call control information indicating theaccess-restricted base station apparatus to be selectable as a basestation apparatus of handover destination, determines theaccess-restricted base station apparatus to be selectable as a handoverdestination cell.

(7) Yet further, a base station apparatus in accordance with theinvention is a base station apparatus applied to a mobile communicationsystem that includes an access-restricted base station apparatus forperforming communication with a mobile station apparatus registered inadvance and a mobile station apparatus in a priority call communication,the base station apparatus comprising: a priority-call controlinformation generation section that, when access-class informationindicating a priority of communication of the mobile station apparatusincludes information indicating a priority call as a call type,generates priority-call control information at least indicating theaccess-restricted base station apparatus to be selectable as a basestation apparatus of a handover destination; and a transmission sectionthat transmits the priority-call control information to the mobilestation apparatus.

(8) Further, a mobile communication system in accordance with theinvention is a mobile communication system, comprising: anaccess-restricted base station apparatus for performing communicationwith a mobile station apparatus registered in advance and a mobilestation apparatus in a priority call communication; a mobile stationapparatus according to any one of claims 1 to 5; and a base stationapparatus.

(9) Still further, a mobile communication system in accordance with theinvention is a mobile communication system, comprising: anaccess-restricted base station apparatus for performing communicationwith a mobile station apparatus registered in advance and a mobilestation apparatus in a priority call communication; a mobile stationapparatus according to claim 6; and a base station apparatus accordingto claim 7.

Advantages of the Invention

According to the invention, selection as to whether or not to performmeasurement of the channel state between a mobile station apparatus anda small base station apparatus is made, depending on the priority ofcommunication. Accordingly, unnecessary measurement of the channel statebetween the mobile station apparatus and the small base stationapparatus and unnecessary handover are restricted, and the powerconsumption by the mobile station apparatus is reduced, and on the otherhand, necessary measurement of the channel state between the mobilestation apparatus and the small base station apparatus can be performed.As a result, the range of coverage can be widened, and a call loss and acall disconnection can be avoided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an example of a reception device of amobile station apparatus in a first embodiment in accordance with theinvention.

FIG. 2 is a block diagram showing an example of a transmission device ofthe mobile station apparatus in the first embodiment in accordance withthe invention.

FIG. 3 is a block diagram showing an example of a reception device of abase station apparatus in the first embodiment in accordance with theinvention.

FIG. 4 is a block diagram showing an example of a transmission device ofthe base station apparatus in the first embodiment in accordance withthe invention.

FIG. 5 is a sequence chart illustrating about the measurement of aneighboring cell and a measurement report in the first embodiment inaccordance with the invention.

FIG. 6 is a flowchart showing a processing procedure of a originatedcall processing of a priority call in the mobile station apparatus inthe first embodiment in accordance with the invention.

FIG. 7 is a flowchart showing a processing procedure of measurementprocessing of a neighboring cell in a priority call communication in themobile station apparatus in the first embodiment in accordance with theinvention.

FIG. 8 is a block diagram showing an example of a reception device of amobile station apparatus in a second embodiment in accordance with theinvention.

FIG. 9 is a block diagram showing an example of a transmission device ofthe mobile station apparatus in the second embodiment in accordance withthe invention.

FIG. 10 is a block diagram showing an example of a reception device of abase station apparatus in the second embodiment in accordance with theinvention.

FIG. 11 is a sequence chart illustrating about selection of areconnection cell and a request for reconnection in the secondembodiment in accordance with the invention.

FIG. 12 is a flowchart showing a processing procedure of reconnectioncell selection processing in the mobile station apparatus in the secondembodiment in accordance with the invention.

FIG. 13 is a sequence chart showing cell selection at the time oftermination of a priority call in the second embodiment in accordancewith the invention.

FIG. 14 is a flowchart showing a processing procedure of a cellselection processing at the time of termination of the priority call inthe mobile station apparatus in the second embodiment in accordance withthe invention.

FIG. 15 is a block diagram showing an example of a transmission deviceof a base station apparatus in a third embodiment in accordance with theinvention.

FIG. 16 is a sequence chart illustrating about a processing procedure ofneighboring cell measurement processing in the third embodiment inaccordance with the invention.

FIG. 17 is a sequence chart illustrating about conventional neighboringcell measurement and a conventional measurement report.

FIG. 18 is a flowchart showing a processing procedure of neighboringcell measurement processing during communication in a conventionalmobile station apparatus.

BEST MODES FOR CARRYING OUT THE INVENTION

Next, embodiments in accordance with the invention will be described,referring to the drawings. Physical channels used in EUTRA and AdvancedEUTRA include a broadcast information channel, uplink data channel,downlink data channel, downlink shared control channel, uplink sharedcontrol channel, random access channel, synchronization signal, downlinkreference signal, and the like. It is possible that more physicalchannels will be added or the channel structure will be modified in thefuture, however, the description of respective embodiments in accordancewith the invention will not be affected, and accordingly descriptionabout it will be omitted. Further, reference signals include downlinkreference signals and uplink reference signals. Because the physicalchannels related to the respective embodiments in accordance with theinvention are synchronization signals, broadcast information channels,and downlink reference signals, description of details of other physicalchannels will be omitted.

Synchronization signals are used by a base station apparatus to detect amobile station apparatus immediately. Synchronization signals includethree kinds of primary synchronization signals and secondarysynchronization signals in which 31 kinds of codes are alternatelyallocated, wherein cell IDs in a number of 504 for identification ofbase station apparatuses and frame timings for radio synchronization areshown by combination of the primary synchronization signals and thesecondary synchronization signals.

A broadcast information channel (BCH: Broadcast Channel) is transmittedfor a purpose of notifying a control parameter to be used commonly bymobile station apparatuses in a cell. Further, BCH is categorized intoP-BCH (Primary BCH) and D-BCH (Dynamic BCH). As it is predetermined thatP-BCH is transmitted with a certain cycle in terms of time/frequency,and accordingly a mobile station apparatus can receive P-BCH of a cellwhose cell ID has been identified. On the other hand, as for D-BCH,transmission resource thereof is notified using a downlink sharedcontrol channel, and the transmission resource can also be made variablefor individual cells. D-BCH includes global IDs (called also global cellIDs) in a number at least greater than the number of cell IDs andallocated by one for each cell, and area information (called also atracking area or a tracking area ID).

Downlink reference signals are pilot signals transmitted from respectivecells with a certain electrical power in principle. Further, downlinkreference signals are periodically repeated at a certain temporalinterval (for example, one frame). The mobile station apparatus receivesdownlink reference signals at the certain temporal interval, measuresthe reception qualities, and thus uses the downlink reference signals todetermine the reception qualities of the respective cells. Stillfurther, the downlink reference signals are used as reference signalsfor demodulation of downlink data transmitted simultaneously with thedownlink reference signals. Arbitrary sequence may be used for thedownlink reference signals as long as the sequences are uniquelydistinguishable for the respective cells. Downlink reference signals maybe described as DL-RS whose purpose and meaning are the same.

First Embodiment

FIG. 1 is a block diagram showing an example of a reception device of amobile station apparatus in a first embodiment in accordance with theinvention. This reception device 100 includes a reception section 101, areception signal processing section 102, a cell information managementsection 103, a measurement information management section 104, and anantenna 105. A reception signal (a transmission signal from the basestation apparatus) is received by the reception section 101 via theantenna 105. In the reception section 101, the reception signal isdemodulated based on reception control information indicating thechannel schedule. The reception control information includes receptiontimings related to the respective channels, a multiplexing method,resource allocation information, and information related todemodulation. According to the reception control information, thereception section 101 demodulates/decodes the reception signal for eachchannel and outputs the signal to the reception signal processingsection 102.

Cell information and cell type determination information are input tothe cell information management section 103. Cell information includesinformation capable of uniquely identifying a CSG cell for which themobile station apparatus is registered and cell type determinationinformation for distinguishing normal cells from CSG cells. CSG cellsfor which the mobile station apparatus is registered are listed and thelist includes all or a part of, for example, area information, a CSGcell ID (also called a CSG ID), a frequency, a bandwidth, a global ID, acommunication system, GPS information, an IP address, and otherinformation. These pieces of information may be prepared in plural setswhen the mobile station apparatus is registered in plural CSG cells, andfurther, an arbitrary method can be used as the registration method. Asuitable part, of the mobile station apparatus, for storing the cellinformation is a memory in a SIM (Subscriber Identity Module) card,however, not limited thereto.

Further, cell type determination information includes information fordistinguishing CSG cells from normal cells. For example, all or a partof information on a cell ID used only for a CSG cell, a frequency band,the correspondence relationship between a CSG cell identifier obtainedfrom broadcast information and the cell ID, and the like, is included.The cell information management section 103 outputs these pieces ofinformation to the reception signal processing section 102.

Further, mobile station apparatus access-class information is input tothe reception signal processing section 102, as necessary. Mobilestation apparatus access-class information is information fordetermination of the priority to be applied when the mobile stationapparatus performs communication. For example, for a dedicated mobilestation apparatus used for maintenance by an operator, a priority higherthan that of a mobile station apparatus generally and commerciallyavailable. Further, a priority is set also depending on the type of acall, and the priorities of priority calls (emergency calls such as No.110, No. 119, etc. in the case of Japan) are set higher than those ofordinary communications. The higher the priority, the shorter thewaiting time for transmission in originating a call and the higher thepriority allocated to radio resources. In addition, a communicationcontrol such as to perform data communication with a higher transmissionpower and a higher reception power, which is different from that forordinary calls, is applied.

the reception signal processing section 102 processes an input signalfrom the reception section 101 appropriately for each channel, andparticularly performs measurement processing based on the mobile stationapparatus access-class information, the cell information, and the celltype determination information having been input, thereby outputtingnecessary measurement information to the measurement informationmanagement section 104. This ‘measurement information’ includes a cellID detected from a synchronization signal, the reception quality of adownlink reference signal, and area information obtained from broadcastinformation. The reception signal processing section 102 determineswhether to obtain the measurement information on the CSG cell, dependingon the mobile station apparatus access-class information.

Information other than the measurement information processed by thereception signal processing section 102, for example, traffic data ofthe user and the downlink control data, is input to individualprocessing blocks as other information, however, description thereofwill be omitted because it is not related to the invention.

The measurement information management section 104 manages measurementinformation for each cell, and notifies an upper level layer of themeasurement information as measurement result information at anappropriate timing.

FIG. 2 is a block diagram showing an example of a transmission device ofthe mobile station apparatus in the first embodiment in accordance withthe invention. The transmission device 200 includes a measurement reportmessage generation section 201, a transmission signal processing section202, a transmission section 203, and an antenna 204. To the measurementreport message generation section 201, measurement report information isinput at an appropriate timing, according to an instruction by the upperlevel layer. The measurement report message generation section 201generates a measurement report message, based on the measurement reportinformation, and outputs the message to the transmission signalprocessing section 202.

The transmission signal processing section 202 performs appropriatescheduling for the measurement report message from the measurementreport message generation section 201 and other transmission signals.Other transmission signals are uplink user traffic data, uplink controldata, an uplink reference signal, and the like. Data that is output fromthe transmission signal processing section 202 based on the schedulingis output from the transmission section 203, according to transmissioncontrol information, as a transmission signal via the antenna 204. Thetransmission control information includes transmission timings relatedto the respective channels, a multiplexing method, resource allocationinformation, and information on modulation.

In FIGS. 1 and 2, as the other components of the mobile stationapparatus are not related to the present embodiment, the descriptionthereof will be omitted.

FIG. 3 is a block diagram showing an example of a reception device of abase station apparatus in the first embodiment in accordance with theinvention. A reception device 300 includes a reception section 301, areception signal processing section 302, a measurement report messageprocessing section 303, and an antenna 304. A reception signal (atransmission signal from the mobile station apparatus) is received bythe reception section 301 via the antenna 304. In the reception section301, the reception signal is demodulated, based on reception controlinformation indicating the channel schedule. The reception controlinformation includes reception timings related to the respectivechannels for the individual mobile station apparatuses, the multiplexingmethod, the resource allocation information, and information ondemodulation. According to the reception control information, thereception section 301 demodulates/decodes the reception signal for therespective channels, and outputs the signal to the reception signalprocessing section 302. Further, to the reception signal processingsection 302, mobile station apparatus information is input. The mobilestation apparatus information includes mobile station apparatusaccess-class information.

The reception signal processing section 302 sorts input signals bymobile station apparatus, and further appropriately processes the inputsignals for the respective channels. When an input signal is ameasurement report message, the measurement report message is output tothe measurement report message processing section 303. Signals otherthan measurement report messages processed by the reception signalprocessing section 302, for example, traffic data of a user, uplinkcontrol data, other control messages, and the like, are input toindividual processing blocks as other information, however, these piecesof information are not related to the invention, and description thereofwill be omitted.

The measurement report message processing section 303 outputs cellinformation included in the measurement report message and measurementreport information that includes quality information on the downlinkreference signal.

FIG. 4 is a block diagram showing an example of a transmission device ofthe base station apparatus in the first embodiment in accordance withthe invention. The transmission device 400 includes a CSG cellinformation generation section 401, an access-restriction informationmanagement section 402, a transmission signal processing section 403, atransmission section 404, and an antenna 405. Cell type information isinput to the CSG cell information generation section 401. Cell typeinformation is information for determining whether the base stationapparatus is a CSG cell or a normal cell. When the cell type informationis for a CSG cell, the CSG cell information generation section 401generates and outputs CSG cell information to the transmission signalprocessing section 403. When the cell type information is not for a CSGcell (a case of a normal cell), nothing is carried out.

Herein, any CSG cell information enabling the mobile station apparatusto determine the base station apparatus to be a CSG cell is applicable,and the content of the CSG cell information may be arbitrary. Forexample, the CSG cell information may be cell ID information forgeneration of a synchronization signal, CSG cell identifier informationincluded in broadcast information, or information on the transmissionfrequency band.

In the access-restriction information management section 402,information on mobile station apparatuses access-restricted by the basestation apparatus is registered in advance, and the information on theaccess-restricted mobile station apparatuses is set in broadcastinformation. In the transmission signal processing section 403, the CSGcell information and the information on the access-restricted mobilestation apparatuses are input. The transmission signal processingsection 403 performs appropriate scheduling for a transmission signalgenerated based on the CSG cell information from the CSG cellinformation generation section 401 and other transmission signals. Othertransmission signals are downlink user traffic data, downlink controldata, a downlink reference signal, and the like of the respective mobilestation apparatuses.

Data that is output from the transmission signal processing section 403,based on the scheduling, is output by the transmission section 404 as atransmission signal via the antenna 405, according to transmissioncontrol information. The transmission control information includestransmission timings related to the respective channels, themultiplexing method, the resource allocation information, andinformation on modulation.

In FIGS. 3 and 4, since the other components of the base stationapparatus are not related to the present embodiment, description thereofwill be omitted.

FIG. 5 is a sequence chart illustrating about a neighboring cellmeasurement procedure in a priority call communication state and ameasurement report procedure. Herein, a mobile station apparatus belongsto a base station apparatus (a source cell). The mobile stationapparatus receives a synchronization signal-s from the source cell(cell_A)(step S501), a downlink reference signal-s (step S502), andbroadcast information-s (step S503), and further obtains CSG cellinformation from a CSG cell (cell_B) (step S504). In FIG. 5, it isillustrated for simplification such that CSG cell information istransmitted from the CSG cell (cell_B). However, a message of CSG cellinformation is not actually transmitted, and information is transmittedfrom the CSG cell so that a normal cell can be distinguished from a CSGcell by the mobile station apparatus with a physical or controlparameter, wherein the format of the information and the physicalchannel to be used may be arbitrary. For example, it may be cell IDinformation notified by a synchronization signal, CSG cell identifierinformation included in broadcast information notified by a broadcastinformation channel, or information on the frequency band of a detectedsynchronization signal. Further, cells_A to B may be allocated torespective different frequencies or may be based on differentcommunication methods.

After determining the cell_B to be a CSG cell from the CSG cellinformation, the mobile station apparatus may stop decoding/demodulatingof the transmission signal (downlink physical channel) from the CSG cell(cell_B). That is, the downlink reference signal as the object ofmeasurement by the mobile station apparatus at this moment is only thedownlink reference signal-s from the source cell (cell_A).

Herein, the mobile station apparatus performs originated call processing(priority call) upon a request for originating a priority call (stepS505). The mobile station apparatus, which has entered a state ofcommunication (active state) with the source cell (cell_A), following asuccess in the originated call processing (priority call) (step S506),changes the control so as to make the downlink reference signals of alldetected neighboring cells be objects of measurement. That is, at thismoment, downlink reference signals as objects of measurement by themobile station apparatus become the downlink reference signal-s from thesource cell (cell_A) (step S507), and a downlink reference signal-csgfrom the CSG cell (cell_B) (step S508).

The mobile station apparatus performs measurement of neighboring cells,based on the downlink reference signals (step S509), and transmits anobtained measurement result, by including it in a measurement reportmessage, to the source cell (cell_A) (step S510). In FIG. 5, the otherchannels transmitted from the CSG cell are omitted.

Next, the originated call processing (priority call) of the mobilestation apparatus and the details of the procedure of the measurement ofneighboring cells in FIG. 5 are respectively shown in FIGS. 6 and 7.FIG. 6 is a flowchart showing an example of a processing procedure oforiginated call processing (a priority call) in the mobile stationapparatus. In performing origination of a priority call, the mobilestation apparatus performs access-class setting for a priority calldefined in advance (step S601). Further, in the camped base stationapparatus (source cell), confirmation as to whether or not the setaccess-class is prohibited is made based on the access-restrictioninformation set in the broadcast information on the source cell.

It is determined whether or not a priority call is prohibited (stepS602), and when a priority call is prohibited (a cell for testing, acell under construction, etc.), it is determined that origination of acall has failed (step S603), and the process is terminated. On the otherhand, in step S602, when a priority call is not prohibited, the processis continued to start the originated call procedure (priority call)(step S604). In the originated call procedure (priority call), themobile station apparatus transmits the information on the setaccess-class, by including it in a radio signaling message (for example,a layer-3 message), to the base station apparatus.

FIG. 7 is a flowchart showing an example of a processing procedure ofmeasurement of neighboring cells in the mobile station apparatus inaccordance with the invention. The mobile station apparatus receivessignals from neighboring cells (including the source cell) in receivingneighboring cell signals (step S701). Then, it is determined whether ornot cell information can be read out (step S702). If cell informationhas been read out, then the call type is determined (step S703). In acase of a normal call communication, it is determined whether or not aCSG cell is disposed as a neighboring cell and further a signal of anunregistered CSG cell is included in the received signals, based on theCSG cell information (step S704).

In step S704, when an unregistered CSG cell is disposed as a neighboringcell, the measurement processing is performed based on downlinkreference signals of neighboring cells, other than the unregistered CSGcell distinguished by the CSG information, out of detected cells (stepS705).

On the other hand, in step S702, when cell information cannot be readout, for example, when a SIM card is not inserted in the mobile stationapparatus, it cannot be determined whether or not a cell is a registeredCSG cell, and communication permitted then for the mobile stationapparatus is only for a priority call, measurement processing based onthe downlink reference signals of all detected cells is performed (stepS706). Likewise, in a case in a priority call communication in stepS703, or in a case where an unregistered CSG cell is not disposed as aneighboring cell in step S704, measurement processing based on thedownlink reference signals of all the detected cells is performed,regardless of CSG cell information (step S706). The flowchart shown inFIG. 7 is an example of a processing procedure of a mobile stationapparatus, and any other processing procedure other than this may beused, if a method is applied in which a mobile station apparatusperforms determination for switching measurement processing, dependingon CSG cell information and call type, and, based on the determination,decides whether or not to include a CSG cell in cells as objects ofmeasurement.

Further, based on the moving speed of the mobile station apparatus, itis also possible to determine whether or not to include unregistered CSGcells in measurement objects. For example, it is also possible to add,just before step S706, a step in which it is determined whether themobile station apparatus is either stopping or moving at a low speed,and if the mobile station apparatus is either stopping or moving at alow speed, measurement processing is performed based on the downlinkreference signals of all neighboring cells including unregisteredneighboring cells. Further, it is also possible to add a step in which,if the mobile station apparatus is moving at a high speed conversely,measurement processing of CSG cells is not performed even when the CSGcells have been registered. Still further, when a list (also called ablack list) of neighboring cells which are inappropriate as a handoverdestination is notified from the base station apparatus, measurementprocessing on the inappropriate cells may be stopped.

As has been described above, in the first embodiment, in a normal callcommunication state, a mobile station apparatus does not performreception processing nor measurement processing of unregistered CSGcells, which are disposed in the periphery, and transmits a measurementreport message without including measurement report information onunregistered CSG cells in the measurement report message. Further, in apriority call communication state, reception processing and measurementprocessing of downlink signals of CSG cells are performed even when theCSG cells are unregistered, and a measurement report message istransmitted by including measurement report information on theunregistered CSG cells in the measurement report message. Still further,the base station apparatus receives the measurement report messagetransmitted from the mobile station apparatus, and decides the mobilitycontrol of the mobile station apparatus, such as handover, based on themeasurement report information.

According to the first embodiment, the mobile station apparatus canperform appropriate neighboring cell measurement processing, based onthe state of the mobile station apparatus, and in a case of not apriority call, unnecessary measurement report information is nottransmitted to the base station apparatus. Thus, the measurementefficiency of the mobile station apparatus is improved and the powerconsumption is reduced. Further, in a case of a priority call, it ispossible to include unregistered CSG cells in a measurement report as ahandover destination, and thereby the number of times of communicationdisconnect can be decreased. Yet further, as the mobile stationapparatus does not report about unregistered CSG cells by a measurementreport message, the base station apparatus does not need to determineeach time whether a cell is one that permits handover, and therebycalculation processing is simplified. Further, as it is not necessary toallocate radio resources for an unnecessary measurement report, theusage efficiency of the radio resources is improved.

Second Embodiment

Next, a second embodiment in accordance with the invention will bedescribed below. In the second embodiment, a measurement method to beapplied in a case where a priority call communication has terminated(normal termination, reconnection) and a method of deciding the bestneighboring cell, based on the measurement method, will be provided.

FIG. 8 is a block diagram showing an example of a reception device of amobile station apparatus in a second embodiment in accordance with theinvention. A reception device 800 includes a reception section 801, areception signal processing section 802, a cell information managementsection 803, a measurement information management section 804, areconnection cell selection section 805, and an antenna 806. Thedifference from FIG. 1 is that access-restriction information obtainedfrom broadcast information is input to the reconnection cell selectionsection 805, and measurement information being output from the receptionsignal processing section 802 is input to both the measurementinformation management section 804 and the reconnection cell selectionsection 805. Other blocks are the same as those in FIG. 1, and thereforedescription thereof will be omitted.

The access-restriction information that is input to the reconnectioncell selection section 805 is information that is included in thebroadcast information from a base station apparatus and is used toprohibit mobile station apparatuses other than those of a certainaccess-class from camping or performing communication, or, to converselypermit the mobile station apparatuses of the certain access-class toperform camping or communication, wherein the access-restrictioninformation includes information on the restricted access class and arestricted time.

Based on mobile station apparatus access-class information, cellinformation, and cell type determination information, the receptionsignal processing section 802 outputs measurement information necessaryfor selection of a reconnection cell to the reconnection cell selectionsection 805. The reconnection cell selection section 805 selects thebest reconnection cell, based on access-restriction information on thecells indicated by the measurement information, and outputs reconnectioncell information.

FIG. 9 is a block diagram showing an example of a transmission device ofa mobile station apparatus in the second embodiment in accordance withthe invention. The transmission device 900 includes a reconnectionrequest message generation section 901, a transmission signal processingsection 902, a transmission section 903, and an antenna 904. To thereconnection request message generation section 901, reconnectionrequest message information (cell ID before reconnection, mobile stationapparatus access-class information, etc.) is input, according to aninstruction by an upper layer and at an appropriate timing. Thereconnection request message generation section 901 generates areconnection request message, based on the reconnection request messageinformation, and outputs the message to the transmission signalprocessing section 902.

The transmission signal processing section 902 performs appropriatescheduling for the reconnection request message from the reconnectionrequest message generation section 901 and other transmission signals.Other transmission signals are uplink user traffic data, uplink controldata, an uplink reference signal, and the like. Data that is output fromthe transmission signal processing section 902, based on the scheduling,is output by the transmission section 903 as a transmission signal,according to transmission control information and via the antenna 904.The transmission control information includes transmission timingsrelated to the respective channels, a multiplexing method, resourceallocation information, and information on modulation.

In FIGS. 8 and 9, as the other components of the mobile stationapparatus are not related to the present embodiment, description thereofwill be omitted.

FIG. 10 is a block diagram showing an example of a reception device of abase station apparatus in the second embodiment in accordance with theinvention. The reception device 1000 includes a reception section 1001,a reception signal processing section 1002, a reconnection requestmessage processing section 1003, and an antenna 1004. A reception signal(a transmission signal from a mobile station apparatus) is received bythe reception section 1001 via the antenna 1004. The reception signal isdemodulated by the reception section 1001, based on reception controlinformation indicating a channel schedule. The reception controlinformation includes reception timings related to the respectivechannels of each mobile station apparatus, a multiplexing method,resource allocation information, and information related todemodulation. According to the reception control information, thereception section 1001 demodulates/decodes the reception signal for therespective channels, and outputs the signal to the reception signalprocessing section 1002. Further, mobile station apparatus informationis input to the reception signal processing section 1002. The mobilestation apparatus information includes mobile station apparatusaccess-class information.

The reception signal processing section 1002 sorts input signals bymobile station apparatus, and further appropriately processes the inputsignals for the respective channels. When an input signal is areconnection request message, the reconnection request message is outputto the reconnection request message processing section 1003. Signalsother than reconnection request messages processed by the receptionsignal processing section 1002, for example, traffic data of a user,uplink control data, other control messages, and the like, are input toindividual processing blocks as other information, however, these piecesof information are not related to the invention, and description thereofwill be omitted. The reconnection request message processing section1003 outputs reconnection request information (cell ID beforereconnection, mobile station apparatus access-class information, etc.)from the reconnection request message.

In FIG. 10, as other components of the base station apparatus are notrelated to the invention, description thereof will be omitted. Further,the transmission device of the base station apparatus can employ thesame configuration as that in FIG. 4 in the first embodiment.

In addition to the cases of normal termination of communication,termination of a priority call communication may occur whencommunication terminates along with being out of a downlinksynchronization due to deterioration in the radio quality. Herein, inorder to reestablish radio connection, the mobile station apparatusstarts a reconnection procedure including selection of a reconnectioncell and a reconnection request. FIG. 11 is a sequence chartillustrating a processing procedure of selection of a reconnection celland a procedure of requesting reconnection, in a case where a statebeing out of synchronization has occurred in a state of a priority callcommunication. Herein, it is assumed that the mobile station apparatusbelongs to the base station apparatus (source cell_A) and is in a stateof a priority call communication (step S1101).

In FIG. 11, suppose that a state being out of synchronization hasoccurred due to deterioration in the radio environment (step S1102). Atthis moment, the mobile station apparatus receives signals from all theneighboring cells (including a source cell), and tries reconnection to acell with the best reception quality. That is, as shown in FIG. 11, whena source cell (cell_A), a CSG cell (cell_B), and a neighboring cell(cell_C) are present, the mobile station apparatus receives asynchronization signal-s (step S1103), a downlink reference signal-s(step S1104), and broadcast information-s (step S1105) from the sourcecell (cell_A). The mobile station apparatus receives a synchronizationsignal-csg (step S1106), a downlink reference signal-csg (step S1107),and broadcast information-csg (step S1108) from the CSG cell (cell_B).

Further, the mobile station apparatus receives a synchronizationsignal-n (step S1109), a downlink reference signal-n (step S1110), andbroadcast information-n (step S1111) from the neighboring cell (cell_C).Herein, even when the mobile station apparatus has obtained CSG cellinformation, if the call type before the state being out ofsynchronization is a priority call, the mobile station apparatusreceives the signals from the CSG cell, and performs measurementprocessing on the downlink reference signal-csg. Then, based on thereconnection cell selection processing, the mobile station apparatusselects a cell with the best quality of the downlink measurement (stepS1112), and transmits a reconnection request message to the selectedcell (step S1113).

FIG. 11 shows an example of a case where the CSG cell (cell_B) isassumed to be the best cell. Although, actually, a random accessprocedure is necessary prior to the reconnection request message, it isomitted in FIG. 11 for simplification. The cells_A to C may be allocatedto respective different frequencies, and may be based on respectivedifferent communication methods.

FIG. 12 is a flowchart showing an example when the mobile stationapparatus performs a processing procedure of selecting a reconnectioncell in FIG. 11. When the mobile station apparatus detects an occurrenceof the state being out of a downlink synchronization in a priority callcommunication with an arbitrary base station apparatus (a source cell),the mobile station apparatus first selects the best cell at the time ofthe occurrence of the state being out of downlink synchronization, andreceives a signal from a neighboring cell (including the source cell)for performing reconnection (step S1201). Next, it is determined whetheror not cell information can be read out (step S1202). If cellinformation is read out, then the call type is determined, based on thelast priority of a call in communication before reconnection (stepS1203). If the last call type is a normal call, it is determined whetheror not a CSG cell is disposed as a neighboring cell and a signal of anunregistered CSG cell is included in reception signals, based on the CSGcell information (step S1204).

In step S1204, if an unregistered CSG cell is disposed as a neighboringcell, measurement processing is performed, based on the downlinkreference signals of neighboring cells, out of detected cells, otherthan the unregistered CSG cell distinguished by CDS information (stepS1205).

On the other hand, in step S1202, if cell information cannot be readout, for example, in a case where a SIM card is not inserted in themobile station apparatus, it cannot be determined whether or not a cellis a registered CSG cell, and further, communication permitted for themobile station apparatus is only by a priority call. Therefore,measurement processing is performed, based on the downlink referencesignals of all the detected cells (step S1206). Likewise, in step S1203,if the call type just before is a priority call, or, in step S1204, ifno unregistered CSG cell is disposed as a neighboring cell, measurementprocessing is performed, based on the reference signals of all thedetected cells, regardless of the CSG cell information (step S1206).Next, based on a result by one of the above-described measurementprocessings, the best one cell is selected (step S1207). Next,access-restriction information on the selected best cell andaccess-class information of the mobile station apparatus are compared(step S1208). If communication by this access-class is prohibited, thenthe next best cell is reselected as the best cell (step S1209), andconfirmation processing as to whether the cell is a prohibited cell isrepeated. On the other hand, in step S1208, if communication at thisaccess-class is not prohibited with regard to the best cell, theselected cell is established as the reconnection cell, and theprocessing is terminated.

The flowchart shown in FIG. 12 is an example of a processing procedureof the mobile station apparatus, and it is possible to use any otherprocessing procedure by a method in which the mobile station apparatusmakes determination for switching the measurement processing dependingon the CSG cell information and the call type, decides whether or notcells as objects of measurement include CSG cells, based on thedetermination, and can determine whether or not it is prohibited toaccess a cell which has been determined to be the best cell as a resultof the measurement. Further, based on the moving speed of the mobilestation apparatus, it is also possible to determine whether or not toinclude unregistered CSG cells in objects of measurement. For example,it is also possible to add a step, just before step S1206, thatdetermines whether the mobile station apparatus is stopping or moving ata low speed, and if the mobile station apparatus is stopping or movingat a low speed, then performs measurement processing based on thedownlink reference signals of all neighboring cells includingunregistered CSG cells. It is also possible to add a step that, when themobile station apparatus is moving at a high speed conversely, does notperform measurement processing of CSG cells even if the CSG cells havebeen registered. Further, when a list (also called a black list) ofneighboring cells that are inappropriate for reconnection has beennotified, the measurement processing on the inappropriate cells may bestopped. Still further, in a case of performing a handover procedure bya network instruction or a control procedure for switching to a circuitswitching network, in a priority call communication, it is possible toapply a procedure similar to the procedure in FIG. 12.

FIG. 13 is a sequence chart showing a cell selection procedure to beperformed at the time of a cell priority call termination after a normaltermination of a priority call communication, wherein it is assumed thatthe mobile station apparatus belongs to the base station apparatus(source cell (cell_A)) and is in a state of a priority callcommunication (step S1301). Herein, it is assumed that the priority callcommunication is terminated by a request for releasing the radioconnection by a layer-3 signaling message (step S1302). At this time,while distinguishing CSG cells from normal cells other than the CSGcells, the mobile station apparatus performs measurement of the downlinkreference signals of cells other than the CSG cells. That is, as shownin FIG. 13, when a source cell (cell_A), a CSG cell (cell_B), and aneighboring cell (cell_C) are present, the mobile station apparatusreceives, from the source cell (cell_A), a synchronization signal-s(step S1303), a downlink reference signal-s (step S1304), and broadcastinformation-s (step S1305). Further, the mobile station apparatusreceives, from the neighboring cell (cell_C), a synchronization signal-n(step S1307), a downlink reference signal-n (step S1308), and broadcastinformation-n (step S1309). Still further, after receiving CSG cellinformation from the CSG cell (cell_B) (step S1306) and determining thatcell_B is a CSG cell, the mobile station apparatus may stop theprocessing of receiving a transmission signal (downlink physicalchannel) from the CSG cell (cell_B).

FIG. 13 illustrates for simplification such that CSG cell information istransmitted from the CSG cell (cell_B). However, actually, a message ofCSG cell information is not transmitted, but information is transmittedfrom the CSG cell so as to enable the mobile station apparatus todistinguish a normal cell from a CSG cell physically or by a controlparameter, and the format thereof and the physical channel to be usedmay be arbitrary. For example, the information may be cell IDinformation notified by a synchronization signal, CSG cell identifierinformation included in broadcast information notified by a broadcastinformation channel, or information on the frequency band of a detectedsynchronization signal. In FIG. 13, other channels transmitted from theCSG cell are omitted.

Based on the cell selection processing to be performed at the time of apriority call termination, the mobile station apparatus selects a cellof the best downlink measurement quality other than CSG cells (stepS1310), and tries camping of the selected cell. Further, cells_A to Cmay be allocated to respective different frequencies, and may be basedon different communication methods.

FIG. 14 is a flowchart showing an example of a procedure of cellselection processing at the time of priority call termination in theinvention to be performed when the mobile station apparatus normallyterminates a priority call communication. In receiving signals fromneighboring cells after the termination of priority call communication,the mobile station apparatus receives signals from the neighboring cells(including the source cell) (step S1401). Next, it is determined whetheror not cell information can be read out (step S1402). If cellinformation has been read out, then it is determined whether or not CSGcells are disposed as neighboring cells and also whether or not a signalof an unregistered cell is included in reception signals, based on theCSG cell information (step S1403). In step S1403, if an unregistered CSGcell is disposed as a neighboring cell, then measurement processing isperformed, based on downlink reference signals of neighboring cells, outof the detected cells, other than the unregistered CSG celldistinguished by the CSG information (step S1404).

On the other hand, if cell information cannot be read out in step S1402,for example, in a case where a SIM card is not inserted in the mobilestation apparatus, as it is not possible to determine whether or not aCSG cell is a registered CSG cell, measurement processing is performed,based on the downlink reference signals of all the detected cells (stepS1405). Likewise, if no unregistered CSG cells are disposed asneighboring cells in step S1403, measurement processing is performed,based on the downlink reference signals of all the detected cells,regardless of the CSG cell information (step S1405).

The mobile station apparatus selects a cell with the highest measurementquality as the best cell, based on a measurement result obtained by themeasurement processing in step S1404 or step S1405 (step S1406). Next,the access-restriction information on the best cell having been selectedand the access-class information on the mobile station apparatus arecompared (step S1407), and if communication at this access class isprohibited, the mobile station apparatus selects again the next-bestcell as the best cell (step S1408), and repeats determination as towhether or not the cell is a prohibited cell. On the other hand, ifcommunication at this access class is not prohibited for the best cell,the mobile station apparatus establishes the selected cell as a cell forcamping target and terminates the processing.

The flowchart in FIG. 14 is an example of a processing procedure of themobile station apparatus, and a processing procedure other than this maybe used, based on a method in which the mobile station apparatus, aftertermination of the priority call communication and according to the CSGcell information, can determine whether or not cells as measurementobjects are CSG cells, and further can determine, as a result of themeasurement, whether or not the cell having been determined to be thebest cell is prohibited for access. Further, it is also possible todetermine whether or not to include unregistered CSG cells inmeasurement objects, based on the moving speed of the mobile stationapparatus. For example, it is also possible to add a step, just beforestep S1405, that determines whether or not the mobile station apparatusis stopping or moving at a low speed, and if the mobile stationapparatus is stopping or moving at a low speed, performs measurementprocessing, based on the downlink reference signals of all theneighboring cells including unregistered CSG cells. Further, it is alsopossible to add a step that, if the mobile station apparatus is movingat a high speed conversely, does not perform measurement processing ofany CSG cell even if the CSG cell has been registered.

As has been described above, in the second embodiment, at the time ofreconnection, the mobile station apparatus can select a cell as areconnection target even when the cell is unregistered, and transmit areconnection message to the unregistered CSG cell. Further, the basestation apparatus receives the reconnection request message of themobile station apparatus, and can permit the CSG cell as a reconnectiondestination.

Further, in the second embodiment, in addition to the advantages in thefirst embodiment, it is possible for the mobile station apparatus toselect an unregistered CSG cell as a reconnection cell at the time ofreconnection procedure, thus increase the success probability ofreconnection, and improve the communication quality.

Third Embodiment

A third embodiment in accordance with the invention will be describedbelow. In the third embodiment, provided is a method in which a basestation apparatus provides a mobile station apparatus in a priority callcommunication, with information on a peripheral base station apparatus,and thereby a more effective measurement can be attained. In the thirdembodiment, the reception device and the transmission device of themobile station apparatus, and the reception device of the base stationapparatus, can have the same configurations as those in the firstembodiment.

FIG. 15 is a block diagram showing an example of a transmission deviceof the base station apparatus in the third embodiment in accordance withthe invention. A transmission device 1500 includes a CSG cellinformation generation section 1501, an access-restriction informationmanagement section 1502, a priority-call control information generationsection 1503, a transmission signal processing section 1504, atransmission section 1505, and an antenna 1506. FIG. 15 is the same asFIG. 4 except that priority-call control information is input from thepriority-call control information generation section 1503 to thetransmission signal processing section 1504, and accordingly descriptionwill be omitted.

Access-class information of the mobile station apparatus notified fromthe mobile station apparatus is input to the priority-call controlinformation generation section 1503. If the access-class information ofthe mobile station apparatus includes information indicating a prioritycall as a call type, priority-call control information, which has beenregistered in advance in the priority-call control informationgeneration section 1503, is input to the transmission signal processingsection 1504. The priority-call control information at least includesinformation on peripheral base station apparatuses selectable as ahandover destination cell (also called a white list, and including cellIDs and frequency band information). The transmission signal processingsection 1504 performs appropriate scheduling for the transmission signalwhich is generated based on the CSG cell information from the CSG cellinformation generation section 1501, the priority-call controlinformation, and other transmission signals. In FIG. 15, othercomponents of the base station apparatus are not related to theinvention, and are accordingly omitted.

FIG. 16 is a sequence chart showing a procedure of neighboring cellmeasurement in a priority call communication state and the measurementreport procedure in the third embodiment. In FIG. 16, up to the timewhen the mobile station apparatus performs originated call processing(priority call) upon a originated call request of a priority call andbecomes in a state of communication (active state) with the source cell(cell_A), the process is the same as that in FIG. 5 (steps S1601 toS1605). In a state that the mobile station apparatus is in the prioritycall communication (step S1606), the source cell transmits priority-callcontrol information (step S1607). The priority-call control informationis transmitted in a layer-3 signaling message, using a broadcastinformation channel or a downlink data channel.

The mobile station apparatus changes the control so as to make thedownlink reference signals of peripheral base station apparatusesindicated in the received priority-call control information be objectsof measurement (steps S1608 and S1609). That is, a cell indicated ininformation on a peripheral base station apparatus is subjected toneighboring cell measurement processing regardless of the cell typethereof (step S1610). Then, a measurement result obtained by themeasurement processing is included in a measurement report message to betransmitted to the source cell (cell_A) (step S1611). FIG. 16 shows acase where the CSG cell (cell_B) is indicated in peripheral base stationinformation, wherein downlink reference signals which are made by themobile station apparatus to be measurement objects are a downlinkreference signal-s from the source cell (cell_A) (step S1608) and adownlink reference signal-csg from the CSG cell (cell_B) (step S1609).

In FIG. 16, other channels transmitted from CSG cells are omitted.Further, when a list (also called a black list) of inappropriateneighboring cells as a handover destination is notified from the basestation apparatus, measurement processing on the inappropriate cells maybe stopped. Further, as neighboring cell information indicated ininformation on peripheral base station apparatus, a plurality of piecesof cell information may be individually indicated, or a frequency bandto be measured may be indicated. Still further, the cells_A to B may beallocated to respective different frequencies or may be based ondifferent communication methods.

As has been described above, in the third embodiment, for the mobilestation apparatus, cells to be objects of measurement in a priority callcommunication state are indicated in peripheral base apparatusinformation by the base station apparatus, and the mobile stationapparatus can perform neighboring cell measurement of the indicatedcells. Further, the base station apparatus transmits, to the mobilestation apparatus, information on peripheral base station apparatusesbeing appropriate handover destinations. Still further, the base stationapparatus receives a measurement report message transmitted by themobile station apparatus, and decides the mobility control of the mobilestation apparatus, such as handover, based on the measurement reportinformation.

Further, in the third embodiment, for the mobile station apparatus,neighboring cells to be objects of measurement are indicated in thepriority call communication state, unnecessary measurement reportinformation is not transmitted to the base station apparatus, andthereby the measurement efficiency by the mobile station apparatus isimproved and the power consumption is reduced. Yet further, becauseappropriate peripheral base station apparatuses are provided as handoverdestinations, the success probability of handover is increased, and thecommunication quality is improved.

(A) Further, in accordance with the invention, the following embodimentis also applicable. That is, a mobile station apparatus in accordancewith the invention can be applied to a mobile communication system thatincludes a small base station apparatus which makes, in normal case,only mobile station apparatuses registered in advance accessible, and onthe other hand, makes, in emergency case, unregistered mobile stationapparatuses accessible, wherein the mobile station apparatus selectswhether or not to perform measurement of the channel state between themobile station apparatus and the small base station apparatus, accordingto the priority of communication.

In such a manner, as a mobile station apparatus selects, according tothe priority of communication, whether or not to perform measurement ofthe channel state between the mobile station apparatus and a small basestation apparatus, unnecessary measurement of the channel state betweenthe mobile station apparatus and a small base station apparatus andunnecessary handover are restricted, and the power consumption by themobile station apparatus is reduced, and on the other hand, necessarymeasurement of the channel state between the mobile station apparatusand a small base station apparatus can be performed. As a result, therange of coverage can be widened, and a call loss and a calldisconnection can be avoided.

(B) Further, in performing reconnection, the mobile station apparatus inaccordance with the invention selects whether or not to performmeasurement of the channel state between the mobile station apparatusand the small base station apparatus, according to the priority ofcommunication having been performed just before.

In such a manner, in performing reconnection, as the mobile stationapparatus selects whether or not to perform measurement of the channelstate between the mobile station apparatus and the small base stationapparatus, according to the priority of the communication having beenperformed just before, unnecessary measurement of the channel statebetween the mobile station apparatus and a small base station apparatusand unnecessary handover are restricted, and the power consumption bythe mobile station apparatus is restricted, and on the other hand,necessary measurement of the channel state between the mobile stationapparatus and a small base station apparatus can be performed. As aresult, the range of coverage can be widened, and a call loss and a calldisconnection can be avoided.

(C) Still further, when the priority of the above-describedcommunication is high, the mobile station apparatus in accordance withthe invention performs measurement of the channel state between themobile station apparatus and the small base station apparatus, and onthe other hand, when the priority of the communication is low, themobile station apparatus does not perform measurement of the channelstate between the mobile station apparatus and the small base stationapparatus.

In such a manner, when the priority of communication is high, the mobilestation apparatus performs measurement of the channel state between themobile station apparatus and the small base station apparatus, and onthe other hand, when the priority of the communication is low, themobile station apparatus does not perform measurement of the channelstate between the mobile station apparatus and the small base stationapparatus. Consequently, for a priority call, an unregistered small basestation apparatus can be made an object of measurement of the channelstate so that call disconnection can be avoided. On the other hand, fora call that is not a priority call, unnecessary measurement informationon the channel state is not transmitted to the base station apparatus,which improves the efficiency of measurement of the channel and reducesthe power consumption.

(D) Yet further, when communication has been normally terminated, themobile station apparatus in accordance with the invention does notperform measurement of the channel state between the mobile stationapparatus and the small base station apparatus.

In such a manner, when communication has been normally terminated, themobile station apparatus does not perform measurement of the channelstate between the mobile station apparatus and the small base stationapparatus. Consequently, unnecessary measurement information on thestate of the channel is not transmitted to the base station apparatus,which improves the efficiency of measurement of the channel and reducesthe power consumption.

(E) Further, the mobile station apparatus in accordance with theinvention includes at least a cell information management section thatoutputs cell type determination information for distinguishing a normalbase station apparatus from the small base station apparatus, and areception signal processing section that selects whether or not toperform measurement of the state of the transfer path between the mobilestation apparatus and the small base station apparatus, based on thecell type determination information and access-class informationindicating the priority of communication, and performs measurement ofthe channel state, corresponding to a result of the selection.

In such a manner, the mobile station apparatus selects whether or not toperform measurement of the channel state between the mobile stationapparatus and the small base station apparatus, based on the cell typedetermination information and access-class information indicating thepriority of communication, and performs measurement of the channelstate, corresponding to a result of the selection. Consequently,unnecessary measurement of the channel state between the mobile stationapparatus and a small base station apparatus and unnecessary handoverare restricted, and the power consumption by the mobile stationapparatus is reduced, while necessary measurement of the channel statebetween the mobile station apparatus and a small base station apparatuscan be performed. As a result, the range of coverage can be widened, anda call loss and a call disconnection can be avoided.

(F) Still further, the mobile station apparatus in accordance with theinvention is applied to a mobile communication system that includes asmall base station apparatus which makes only mobile stationapparatuses, which have been registered in advance, accessible in a caseof a normal call, and on the other hand, makes mobile stationapparatuses, which have not been registered, accessible in a case of apriority call. When the mobile station apparatus has receivedpriority-call control information from a base station apparatus in apriority call communication, the information indicating that the smallbase station apparatus is selectable as a base station apparatus of ahandover destination, the mobile station apparatus performs measurementof the channel state between the mobile station apparatus and the smallbase station apparatus.

In such a manner, when the mobile station apparatus has receivedpriority-call control information from a base station apparatus in apriority call communication, the information indicating that the smallbase station apparatus is selectable as a base station apparatus of ahandover destination, the mobile station apparatus performs measurementof the channel state between the mobile station apparatus and the smallbase station apparatus. Consequently, it is possible to performeffective measurement of the channel state.

(G) Yet further, a base station apparatus in accordance with theinvention is applied to a mobile communication system that includes asmall base station apparatus which makes only mobile stationapparatuses, which have been registered in advance, accessible in a caseof a normal call, and on the other hand, makes mobile stationapparatuses, which have not been registered, accessible in a case of apriority call. The base station apparatus includes: a priority-callcontrol information generation section that, in a case whereaccess-class information indicating the priority of the communication ofthe mobile station apparatus includes information indicating a prioritycall as the call type, generates priority-call control information thatat least indicates selectability of the small base station apparatus asa base station apparatus of a handover destination; and a transmissionsection that transmits the priority-call control information to themobile station apparatus.

In such a manner, the base station apparatus, in a case whereaccess-class information indicating the priority of the communication ofthe mobile station apparatus includes information indicating a prioritycall as the call type, generates priority-call control information thatat least indicates selectability of the small base station apparatus asa base station apparatus of a handover destination; and transmits thegenerated priority-call control information to the mobile stationapparatus. Consequently, it is possible to notify the mobile stationapparatus of an appropriate handover destination.

(H) Further, a mobile communication system in accordance with theinvention includes: a small base station apparatus that makes onlymobile station apparatuses, which have been registered in advance,accessible in normal case, and on the other hand, makes unregisteredmobile station apparatuses accessible in non-normal case; any one of themobile station apparatuses described in above (A) to (E); and a basestation apparatus.

By this configuration, selection as to whether to perform measurement ofthe channel state between the mobile station apparatus and the smallbase station apparatus is made depending on the priority ofcommunication. Consequently, unnecessary measurement of the channelstate between the mobile station apparatus and a small base stationapparatus and unnecessary handover are restricted, and the powerconsumption by the mobile station apparatus is reduced, while necessarymeasurement of the channel state between the mobile station apparatusand a small base station apparatus can be performed. As a result, therange of coverage can be widened, and a call loss and a calldisconnection can be avoided.

(I) Still further, a mobile communication system in accordance with theinvention includes: a small base station apparatus that makes onlymobile station apparatuses, which have been registered in advance,accessible in normal case, and on the other hand, makes unregisteredmobile station apparatuses accessible in non-normal case; the mobilestation apparatus described in above (F); and the base station apparatusdescribed in above (G).

By this configuration, when the mobile station apparatus has receivedpriority-call control information from a base station apparatus in apriority call communication, the information indicating that the smallbase station apparatus is selectable as a base station apparatus of ahandover destination, the mobile station apparatus performs measurementof the channel state between the mobile station apparatus and the smallbase station apparatus. Consequently, it is possible to performeffective measurement of the channel state.

In accordance with the invention, it is possible to prepare a pluralityof methods of measuring neighboring cells, corresponding to the priorityof communication by a mobile station apparatus, and provide a method ofswitching them. Further, it is possible to provide a method of measuringthe reception quality of neighboring cells by the mobile stationapparatus and a reporting method, and a base station apparatus, a mobilestation apparatus, a mobile communication system, a program, and arecording medium, which realize these methods.

In the foregoing embodiments, a mobile station apparatus and a basestation apparatus may be controlled by recording, in a computer readablerecording medium, a program for realizing the functions of therespective sections of the mobile station apparatus and the base stationapparatus, or a part of these functions, and having a computer systemread the program recorded in the recording medium and execute theprogram. The ‘a computer system’ referred to herein is assumed toinclude an OS and hardware, such as peripheral devices. Further, ‘acomputer readable recording medium’ refers to a movable medium, such asa flexible disk, a photo-magnetic disk, a ROM, a CD-ROM, etc., or astorage device, such as a hard disk, incorporated in the computersystem. Still further, ‘a computer readable recording medium’ is assumedto include a thing that dynamically holds a program during a short time,such as communication lines for a case of transmitting a program viacommunication lines of a network including the Internet, telephonelines, or the like, and a thing that holds the program for a certaintime, such as a volatile memory inside a computer system as a server ora client in the above-described case. Yet further, the above-describedprogram may be one that realizes a part of the above-describedfunctions, or may be one that realizes the above-described functions bya combination with a program already recorded in the computer system.

Embodiments in accordance with the invention have been described above,referring to the drawings, however, concrete configuration is notlimited to these embodiments, and design and the like that do not departfrom the sprit of the invention are included in the scope of claim forpatent.

REFERENCE NUMERALS

-   100 reception device-   101 reception section-   102 reception signal processing section-   103 cell information management section-   104 measurement information management section-   105 antenna-   200 transmission device-   201 measurement report message generation section-   202 transmission signal processing section-   203 transmission section-   204 antenna-   300 reception device-   301 reception section-   302 reception signal processing section-   303 measurement report message processing section-   304 antenna-   400 transmission device-   401 CSG cell information generation section-   402 access-restriction information management section-   403 transmission signal processing section-   404 transmission section-   405 antenna-   800 reception device-   801 reception section-   802 reception signal processing section-   803 cell information management section-   804 measurement information management section-   805 reconnection cell selection section-   806 antenna-   900 transmission device-   901 reconnection request message generation section-   902 transmission signal processing section-   903 transmission section-   904 antenna-   1000 reception device-   1001 reception section-   1002 reception signal processing section-   1003 reconnection request message processing section-   1004 antenna-   1500 transmission device-   1501 CSG cell information generation section-   1502 access-restriction information management section-   1503 priority-call control information generation section 1504    transmission signal processing section-   1505 transmission section-   1506 antenna

1. A processing method performed in a mobile communication system, theprocessing method comprising: restricting an access for a normal callfrom a mobile station apparatus in a case where a cell of a first basestation apparatus is not registered in a list of the mobile stationapparatus; selecting a cell by a cell selection procedure started by themobile station apparatus, in a case where a radio link failure isdetected, wherein said selecting is based on: a criteria of the cellselection procedure; information, used for indicating accessrestrictions of the mobile station apparatus, the informationbroadcasted on each cells; and  an access class of the mobile stationapparatus, wherein the access class being either:  a first access classapplied for an emergency call, or  other access classes applied forother calls; and treating, in a case where the radio link failure isdetected upon communication of the first access class, the selected cellas an appropriate cell even in a case where the selected cell is a cellbelonging to the first base station not registered in the list; andaccessing the appropriate cell.
 2. A mobile station apparatus in amobile communication system, wherein the mobile communication systemincludes a first base station apparatus capable of restricting an accessfor a normal call from the mobile station apparatus in a case where acell of the first base station apparatus is not registered in a list ofthe mobile station apparatus and a second base station apparatus, thesecond base station apparatus being a different base station apparatusthan the first base station apparatus, the mobile station apparatuscomprising: a first circuitry configured to: select a cell by a cellselection procedure started by the mobile station apparatus, in a casewhere a radio link failure is detected, wherein said selecting based ison: a criteria of the cell selection procedure; information, used forindicating access restrictions of the mobile station apparatus, theinformation broadcasted on each cells; and an access class of the mobilestation apparatus, wherein the access class being either:  a firstaccess class applied for an emergency call, or  other access classesapplied for other calls; and treat, in a case where the radio linkfailure is detected upon communication of the first access class, theselected cell as an appropriate cell even in a case where the selectedcell is a cell belonging to the first base station not registered in thelist; and a second circuitry configured to access the appropriate cell.3. A processing method performed in a mobile station apparatus, whereina mobile communication system includes the mobile station apparatus, afirst base station apparatus capable to restrict an access for a normalcall from the mobile station apparatus in a case where a cell of thefirst base station apparatus is not registered in a list of the mobilestation apparatus, and a second base station apparatus other than thefirst base station apparatus, the processing method comprising:selecting a cell by a cell selection procedure started by the mobilestation apparatus, in a case where a radio link failure is detected,wherein said selecting is based on: a criteria of the cell selectionprocedure; information, used for indicating access restrictions of themobile station apparatus, the information broadcasted on each cells; andan access class of the mobile station apparatus, wherein the accessclass being either:  a first access class applied for an emergency call,or  other access classes applied for other calls; and treating, in acase where the radio link failure is detected upon communication of thefirst access class, the selected cell as an appropriate cell even in acase where the selected cell is a cell belonging to a first base stationnot registered in the list; and accessing the appropriate cell.